EP 0390998 A1 19901010 - Method and apparatus for low voltage plasma arc cutting.
Title (en)
Method and apparatus for low voltage plasma arc cutting.
Title (de)
Verfahren und Einrichtung zum Plasmaschneiden mit niedriger Spannung.
Title (fr)
Procédé et dispositif pour couper au plasma sous tension basse.
Publication
Application
Priority
US 33268489 A 19890403
Abstract (en)
The invention is a method and apparatus that comprises supplying a mixture of gases to a constricted plasma arc. The mixture comprises a gas that will sustain the plasma arc at the lower voltages typical of electric-arc welding and in the absence of a plasma and a gas which provides good heat transfer characteristics. The relative proportion of the gas that will sustain the plasma arc at the lower voltages present in the mixture is large enough to support the plasma arc, and the relative proportion of gas having good heat transfer characteristics present in the mixture is small enough to prevent failure of the arc at the lower voltage. A voltage drop is maintained which is high enough to maintain the plasma arc using the gas mixture while low enough to operate at a substantially constant current using a low voltage constant current power supply.
IPC 1-7
IPC 8 full level
H05H 1/32 (2006.01); B23K 9/29 (2006.01); B23K 10/00 (2006.01)
CPC (source: EP US)
B23K 9/296 (2013.01 - EP US); B23K 10/00 (2013.01 - EP US)
Citation (search report)
- [A] DE 1066676 B 19591008
- [A] US 2960594 A 19601115 - LEE THORPE MERLE
- [A] AT 369305 B 19821227 - MESSER GRIESHEIM GMBH [DE]
- [A] AT 243602 B 19651125 - UNION CARBIDE CORP
- [A] US 3597649 A 19710803 - BYKHOVSKY DAVID GRIGORIEVICH, et al
Designated contracting state (EPC)
BE DE ES FR GB IT SE
DOCDB simple family (publication)
EP 0390998 A1 19901010; CA 1328490 C 19940412; JP H02268980 A 19901102; US 4977305 A 19901211
DOCDB simple family (application)
EP 89310332 A 19891010; CA 608301 A 19890814; JP 23584289 A 19890913; US 33268489 A 19890403